Full Frame Camera on a budget

[Tannin]

^ This is the 24-105/4 at 24mm. It is very soft. That's not representative of the lens, I must have missed focus. But ignore that. Look at the significant barrel distortion - just what you expect at the wide end of a wide-ish zoom. (24mm full frame is equivalent to 15mm on crop.) The top and bottom rails are slightly bowed, but it is very obvious when you look at the 4 x 4 posts - which in reality are pretty close to dead straight. Look also at the top of the palings. Although sloping slightly down the hill (to the left) this is a straight line (which I achieved at the cost of a little extra time and trouble last summer by clamping a straight 3 x 2 to the posts and sitting each paling in turn on it before nailing it on). The barrel distortion, however, bends it quite noticeably. I try to avoid using the 24-105 at 24mm when there is a straight line that will look odd - horizon usually - but I don't fuss too much about it. Life is too short!




^ Now the 16-35/4 at an indicated 24mm. Straight lines are straight. If anything, there might be a tiny bit of pincushion distortion. I should actually have set the tripod at the exact level of the middle rail; but these were all shot from slightly below it. You would expect some measure of barrel distortion at 16mm even with this lens, though I haven't tried that yet.

[Tannin]

APS-C lens on full frame.

If we are going to have barrel distortion, let's do it properly.

(In fact, a fisheye doesn't distort; it simply converts three dimensions to two dimensions in a different way.)




^ Tokina 10-17mm fish at 17mm on a 5D II. Notice the lump on the upper left of the shadow at lower right. Technically, this is known as my ear. Most humans have at least one of them.




^ 16mm and it still works fine. The object at extreme lower left is my thumb, technically known as forgetting just how wide a fish can be 'coz I haven't used it for a while.




^ 15mm, still OK. (The EXIF on the 16mm shot says 15mm. I set these from the scale on the lens, so perhaps it was 15.49mm or something like that. Or maybe the scale is out a bit.)




^ 14mm and apart from the Return of the Thumb, we have vignetting.




^ 13mm. More vignetting. This lens has baffles (some felt-like material I guess) to cut down internal reflections and flare. I know that baffling is common, I don't know if all lenses do it or only some though. If the baffles were not there we would still have vignetting, but it wouldn't transition so suddenly from black to white.




^ 12mm.




^ 11mm.




^ 10mm. Sorry about all the thumbs.

As you can see, an APS-C lens does indeed work on full frame, but the usable zoom range gets the thumbs down. (This is the only non-full frame lens I have now, so no more samples. Besides, you are probably getting as bit bored with the fence by now.)